DES MOINES, Iowa -- The parents of a missing Grinnell College student have called off their search in Iowa but say they're clinging to hope their son is safe somewhere else.

Paul Shuman-Moore, 19, of Chicago was last seen early Sept. 25 heading toward his dormitory at Grinnell. His roommate said he later found a suicide note.

Last week Shuman-Moore's parents returned to Iowa for the first time since their son's disappearance. After meeting with Grinnell police to review the investigation, the parents say they are convinced Shuman-Moore did not kill himself in the Grinnell area.

"There have been hunters going through every stream or gully and farmers going through every field," said Steve Moore, the student's father.

"As time went on, we started hoping he hadn't done anything to himself. That feeling has increased every single day."

The parents said they believe their son is not in Iowa or Chicago, where friends and family have posted thousands of fliers without any response.

Moore acknowledges his searches are "long shots" but will continue to search for his son.

"It's possible he has decided he's embarrassed at all the ruckus he has caused and is afraid to come back," Moore said. "We want to get the message to him that he shouldn't be."

Efforts to find Shuman-Moore initially centered on the Grinnell area in central Iowa. The search at one time included hundreds of volunteers and authorities, three airplanes and three search-and-rescue dog teams.

The family's search has since downsized and shifted to Houston. Shuman-Moore, a music fanatic, was most recently interested in noise music, which has a large following in southeast Texas, his family said. A family friend in Houston has posted signs near music venues but has not received any tips.

At the advice of Shuman-Moore's friends, Moore has also begun contacting music venues across the country, focusing on locations that might feature new music. He asks if they have seen his son and if they will hang a poster in their venue.

"We're hoping that he just decided to take off and is out there somewhere, trying to decide what to do with his life," Moore said. "What his mind set is, we don't know."